In many invasive surgeries utilizing medical devices there is the requirement to use sterile medical devices, for example sterile instruments. This necessitates the use of products that on first use are sterile and subsequently disposed of, or re-sterilised for reuse. Ideally it should not be possible to reuse a medical device until it has been re-sterilised or in the case of single-use only device reuse should be prevented. This can be achieved by a number of means such as mechanically changing the component or utilizing materials that disintegrate after use or materials not compatible with high temperature steam sterilisation.
In some applications a disposable medical device component is connected to a main medical device that is reused. Typically the main medical device uses or controls the operation of the disposable component and as the disposable component represents a small portion of the overall system this part may be discarded to save cost and create a revenue stream. In order to maintain safety by preventing the use of unsterile or contaminated equipment and safeguard product revenue it is imperative to be able to prevent reuse of disposable components.
In some disposable medical products a range of electronic reuse mitigation measures have been described, often implementing complex methods such as RFID chips or polling multiple circuits or communicating with integrated circuits containing software to convey identification and status of the medical device to the controlling system. Whilst these are feasible, their use in a medical device is impeded by the stringent regulations governing the use of software which requires expensive and time consuming software validation activities to achieve the required compliance.
Another known approach to identifying use status for a variety of products is to utilise a onetime fusible element that is blown (open circuit) at the start of or during use. Whilst the use of fuses is practical and readily implemented generally they do not identify the device nor after being blown do they indicate their presence or the integrity of the connection. Thus, it could be possible for the device to be swapped mid-treatment resulting in cross-contamination or replacement of the fuse component.